I have a new problem after I discovered the green raster transistor on the neckboard was loose at the solder joints. After that was fixed and picture has normal colors, I poked around the neck board with my mulitmeter, I took voltage measurements of the 3 raster transistor's emitter, collector, base, then I measure the 4 wires going into the funnel end of the deflection yoke, one of the wires connector when touched by probe made a staticky sound and multimeter reads overload.. I don't know if that was the cause but moments later when I turned around to check the picture it became black and white (or should I say some 2 toned colors). I still have color because turning the pots on the neckboard changes the 2 tones into 2 tones of green, blue, red respectively. And I have color on the on screen display text characters.
My measurements at emitter, collector, base are 13Vdc, 150Vdc, 13Vdc for all three colors. They are hot to touch. I think that means they are in saturation all the time.. maybe they are fried.. Do you know what voltage should the base have normally? I think 13V reading is too huge isn't it? Thus rgb colors in picture are always in max.. The raster transistors are Toshiba C2068
http://www.alldatasheet.com/datasheet-pdf/pdf/108529/TOSHIBA/2SC2068.html
Or the chroma chip is toast? The chroma chip is TA... in photo attached. Please advice. Thank you!!
My measurements at emitter, collector, base are 13Vdc, 150Vdc, 13Vdc for all three colors. They are hot to touch. I think that means they are in saturation all the time.. maybe they are fried.. Do you know what voltage should the base have normally? I think 13V reading is too huge isn't it? Thus rgb colors in picture are always in max.. The raster transistors are Toshiba C2068
http://www.alldatasheet.com/datasheet-pdf/pdf/108529/TOSHIBA/2SC2068.html
Or the chroma chip is toast? The chroma chip is TA... in photo attached. Please advice. Thank you!!
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